Jan 22, 2019 - 06:19 AM
In the manual for the Suburban 5118A on page 4, there is a small section that talks about a thermostat. I will paste what it says below with a link to the manual.
THERMOSTAT AND MANUAL RESET
MODELS SW6PE, SW6PER, SW10PE and SW10PER
The model water heaters listed above are equipped with a high temperature limit
as a cut-off device. Temperature above 180°F will cause manual reset button to
trip shutting down the electric element.
To activate element, the water temperature must be below 110°F, push reset
button to re-activate the electric element. (See Figure 10).